New record from stalagmites shows climate history in Central Asia

Jan 31, 2012

The climate in Central Asia, currently a semiarid region, has varied over the past 500,000 years. An accurate record of the past climate can help scientists understand current climate and better predict how the climate may change in the future. Previous studies with paleoclimate records, such as lake sediments and ice cores, show changes in moisture in the region, but climate history in the region is debated, as some of those records are not high resolution or not well dated.

Cheng et al. describe a new high-resolution, well-dated record of in stalagmites from the Kesang cave in western China. The researchers dated the stalagmites using radioactive thorium dating and then looked at the oxygen isotope record, which provides information on past and precipitation.

The record shows how climate in the region varies with cyclical changes in the Earth's orbit over the past 500,000 years. The authors find that there were some wetter periods in the past, which the authors suggest were caused by moisture carried from the Indian Ocean or other Asian monsoon regions. Currently, moisture to the region mainly comes with westerly winds from the Atlantic Ocean and the Mediterranean and Caspian seas, not from Asian monsoons. These new observations contrast with interpretations based on nearby, but higher-elevation, ice core records. The authors suggest that based on their record, unless anthropogenic effects supersede natural processes, an arid climate will prevail in the region for the next several thousand years.

Explore further: Quakes destroy or damage 83 houses in Philippines

More information: The climatic cyclicity in semiarid-arid central Asia over the past 500,000 years, H. Cheng et al, Geophysical Research Letters, doi:10.1029/2011GL050202 , 2012

add to favorites email to friend print save as pdf

Related Stories

Drilling for climate change

Jan 16, 2012

Researchers aboard the drilling vessel JOIDES Resolution will finish their Mediterranean voyage next week to unearth thousands of centuries of climate data from beneath the ocean floor.

Cave study links climate change to California droughts

Nov 10, 2009

California experienced centuries-long droughts in the past 20,000 years that coincided with the thawing of ice caps in the Arctic, according to a new study by UC Davis doctoral student Jessica Oster and geology professor ...

Recommended for you

Kiribati leader visits Arctic on climate mission

Sep 20, 2014

Fearing that his Pacific island nation could be swallowed by a rising ocean, the president of Kiribati says a visit to the melting Arctic has helped him appreciate the scale of the threat.

NASA catches a weaker Edouard, headed toward Azores

Sep 19, 2014

NASA's Aqua satellite passed over the Atlantic Ocean and captured a picture of Tropical Storm Edouard as it continues to weaken. The National Hurricane Center expects Edouard to affect the western Azores ...

User comments : 0